Hurricane Ivan (1980)
Hurricane Ivan in 1980 developed unusually far northeastward for an Atlantic hurricane. It formed atypically, in association with an upper-level low near the Azores. Moving southwestward, Ivan became the season's ninth named storm and seventh hurricane, reaching peak winds of 105 mph (165 km/h). Along its path, Ivan executed two loops, tracked west-northwestward, and maintained peak winds for about 90 hours. It eventually turned northeastward, and late on October 11 the hurricane was absorbed by an approaching cold front. It did not cause any damage or deaths. Meteorological history The origins of Hurricane Ivan were unusual. In late September, an cold-core low persisted off the southwest coast of Portugal, moving southwestward. Initially, its position was uncertain due to lack of data, although a definitive cyclone was evident by October 1, when it became better organized between the Azores and the Canary Islands. At the time, there was little convection near the center, although the overall cloud pattern cyclonically curved. Despite being over fairly cool water temperatures, the system gradually developed tropical characteristics as it turned northwestward and executed a loop near the Azores. After the cyclone resumed its southwest track, the convection increased and became more organized near the center. Even though it was located beneath an upper-level low, it was sufficiently organized to be designated a tropical depression on October 4 just east of the Azores; shortly thereafter, it intensified into Tropical Storm Ivan. The National Hurricane Center did not initiate advisories on Ivan until late on October 5, by which time the storm was strengthening and developing anticyclonic outflow aloft. Early in Ivan's lifetime, forecasters had difficulty predicting the future of the storm. Ultimately, Ivan largely moved in tandem with the upper-level low above it, while its southwest movement was caused by a building ridge to its north. Late on October 5, an eye developed, and by October 6 Ivan attained hurricane status about 600 miles (970 km) southwest of the Azores. It slowed down as the ridge to its north weakened, and 18 hours after reaching hurricane strength, Ivan peaked with winds of 105 mph (165 km/h). Between October 6 and the 7, Hurricane Ivan executed a tight loop, after which another ridge began intensifying to its east; this allowed the storm to begin a motion to the west-northwest. Ultimately, the intensity did not change for about 90 hours. During that time, the eye fluctuated occasionally as the convection waxed and waned. On October 9, Ivan turned to the north in advance of an approaching cold front and extratropical storm. The next day, the hurricane began weakening as it accelerated northeastward over cooler waters of the far northern Atlantic Ocean. By October 12, the cold front absorbed Hurricane Ivan when it was located about 665 miles (1070 km) west of Ireland. The hurricane formed unusually far northeastward, although later Hurricane Vince in 2005 developed in a similar area. Impact Early in its life, Ivan passed a short distance southeast of the Azores, although it never significantly affected land. As such, there were no reports of casualties or damage in association with the storm. Ivan only posed a threat to shipping interests, and several vessels recorded gale-force winds. References External links *National Hurricane Center *Monthly Weather Review for 1980 Category:Wikipedia Archives